For service and parts needs, visit your dealer. You will receive genuine GM parts and GM-trained and supported service people.
Genuine GM parts have one of these marks:

Vehicle Care
California Proposition 65 WarningAir/Wind Noise
Special Tools
CH-39570 Chassis Ear
GE-41416 Ultrasonic Leak Detector
Warning: Refer to Assistant Driving Warning in the Preface section.
To analyze a reported windnoise condition, test drive the vehicle to
determine the origin of the noise.
Choose a regular route with smooth and strai ...
Water Management Description and Operation
Plenum Water Flow Direction and Cleaning
A large percentage of water will flow off the windshield area into the plenum
chamber drain system and then down the outside on the
plenum to the underside of the vehicle. To ensure that the plenum chamber water
management system performs properly, the ...
StabiliTrak® System
The vehicle has a vehicle stability enhancement system called StabiliTrak. It
is an advanced computer controlled system that assists with directional control
of the vehicle in difficult driving conditions.
StabiliTrak activates when the computer senses a difference between the intended
path, ...